1. Field of the Invention
The present invention relates to an apparatus used to manufacture a semiconductor device, and more particularly, to a semiconductor manufacturing apparatus having a controller detecting function of a filter.
2. Description of the Related Art
Most processes for manufacturing a semiconductor device require the use of chemical solutions. In particular, a chemical and mechanical polishing (CMP) apparatus used to planarize a highly integrated semiconductor device uses a slurry as a polishing agent. Such a slurry generally contains impurities, e.g., clustered impurities, in a predetermined size. These impurities contained in the slurry are then filtered by a filter, and the filtered slurry is used for a real process. However, once a filter has been used for a long period of time, the filtering function of the filter deteriorates. Accordingly, it takes an increased period of time to filter a predetermined amount of slurry.
FIG. 1 is a schematic view of a conventional CMP apparatus. Here, reference a represents a service area where the CMP apparatus is repaired, and reference b represents a clean room area where a real process is performed. Thus, the service area a and the clean room area b are separated and the concentration of particles in the atmosphere is also different in each area.
Referring to FIG. 1, within the service area a there is a tank 10 that contains a chemical solution 15 such as slurry, a pump 20 for circulating the chemical solution in the tank 10, and a filter for filtering impurities in the chemical solution discharged from the pump 20. Usually, the pump 20 is a diaphragm pump having an air inlet 23 and an air outlet 26. Also, a main body 30, i.e., a chemical mechanical polisher, is installed in the clean room area b. An outlet of the filter 35 is connected to the main body 30 to provide a part of the filtered chemical solution, i.e., a part of filtered slurry, to the main body 30. As the period of time that the filter 35 has been used increases, the filtering function of the filter 35 deteriorates. Also, as the functioning of the filter 35 decreases, the operating cycle of the pump 20 becomes longer. Also, in the worst case, the filter 35 may become clogged, so that the process in the main body 30, i.e., the CMP process, cannot be performed.
In the above-described conventional CMP apparatus, an operator must periodically check the operating cycle of the filter 35 installed in the service area and must take the time to replace the filter when necessary. However, visual and aural checking of the operating cycle of the pump 20 can be inaccurate. Thus, a set maximum safe period of use for a filter 35 is predetermined, and when the actual period of time for which the filter 35 has been used reaches this set maximum safe usable period, the filter 35 should be replaced. However, all filters have different life spans, and so it is difficult to differentiate the maximum actual usable period for each filter. Thus, it is difficult to efficiently use the filter and to prevent problems caused by the clogging of the filter or the discarding of usable filters.